Computational model and simulation of the solid-state sintering process as a thermal treatment for metal extrusion additive manufacturing: Microstructural and Multiphysics approach

A numerical model has been developed to simulate microstructure evolution in stainless steel 316L components produced via Metal Extrusion Additive Manufacturing (MExAM). The model integrates key phenomena, including heat conduction, mechanical fields influenced by gravity, and phase-field equations, offering a robust framework to understand and control changes in thermomechanical properties during pressureless solid-state sintering. Advanced numerical techniques, such as the Finite Element Method (FEM) and the Physics-based Preconditioned Jacobian-free Newton-Krylov Method, were employed to solve the complex nonlinear system efficiently. Validation against literature data demonstrated the model’s accuracy and reliability, while tests across varying particle sizes highlighted its adaptability. Simulation results underscore the model’s potential for optimizing sintered materials by providing detailed insights into microstructural, thermal, and mechanical behavior.